The In-Laws
by SeriesTherapy
Summary: "Are you seriously telling me this over the phone? Couldn't you wait until I got home before dropping the bomb that you're dating Beckett's dad?" A little story set in season 4, for #CastleFanFicMonday
1. Chapter 1

"Are you kidding me?!"

Richard Castle's voice echoed throughout the homicide floor of the 12th precinct, causing several detectives and officers to turn their heads, trying to see what elicited such a reaction in the writer. But he couldn't care less what they thought. His attention was focused on Detective Kate Beckett, who was sitting at her desk across the crowded bullpen, holding her phone up to her ear. She looked every bit as perplexed as he imagined he must.

Agitated, he turned around as his mother's voice rang in his ear, reclaiming his attention.

"Oh, Richard, don't be melodramatic, it's not a good look on you," she said in a sing-song voice.

"Are you seriously telling me this over the phone? Couldn't you wait until I got home before dropping the bomb that _you're dating Beckett's dad?_ "

As soon as the words were out of his mouth, the officers closest to him openly stared at him; some of them sporting sly smiles, while others gasped comically. Castle paid them no mind, but retreated further down the hall, nevertheless.

"Oh, that's because we were planning on hosting a dinner tonight, at the loft," Martha continued calmly.

"Tonight?" he questioned. "What's the hurry?"

"There's something we want to tell both of you," Martha said calmly.

Unbelievable. His mother was something out of this world. She was inviting him into his own home, just because she wanted to tell them… _Wait a minute…_

"Wait, both of us?"

"Yes, of course," Martha answered matter-of-factly. "Jim's on the phone with Katherine as we speak."

Castle risked a glance into the bullpen and found Beckett sitting slack-jawed in her chair, pale as a ghost, her eyebrows raised to her hairline.

"Mother, I don't think it's a good idea—"

"Dinner's at seven. Don't be late," she said, hanging up.

Castle took a moment to gather his thoughts, inhaling deeply and counting to three before letting the air exit through his nose. How could this have happened? He was awfully familiar with his mother's history with men, and even he had to admit that Jim was undoubtedly an improvement compared to Martha's past beaus.

However, something didn't add up. He was having a hard time believing that someone as serious and reserved as Jim Beckett could be a match for his eccentric mother. Granted, Castle had only met him on a couple of occasions, neither of which had been very happy. The first one had been at his loft, when Jim asked him for his help to make Kate see reason regarding her mother's case. And the second one, just a couple of days later, was even more somber, in the hospital waiting room as Kate was in surgery, fighting for her life. He hadn't seen Jim Beckett again after that fateful day in the hospital, but apparently, his mother had made quite an impression on him.

But how could she do something like this? Martha knew all about her son's feelings for Kate. He had shared with her every thought, every single development in his remarkably complicated relationship with the detective. During those talks, his mother was his confidant, his go-to person in matters of heart. He even told her about the conversation at the swings, and they spent the evening debating what Kate's words could have meant for them. Castle told her everything, and now she just crushed any chance of a relationship between Beckett and him. How could she? After all the progress that Kate… _Oh, crap. Kate._

If this situation was hard for Castle to wrap his head around, he couldn't fathom what his partner was feeling. He was used to his mother's flings by now, but as far as he knew, Jim hadn't seen anyone since Johanna's death. Whatever he thought about Martha's love life now had to take a second place; Kate's well-being had to come first. Taking a deep breath, Castle squared his shoulders and headed to the desk he unofficially shared with Beckett.

Judging by the frown on her face, Castle knew that his mother was right about who Kate was speaking with. She didn't notice his approach, thoroughly engrossed in the phone call. As he arrived at the desk, Castle overheard the end of her conversation.

"No, I'm fine. I'm sure, Dad. Yes, I'll see you tonight."

As she hung the phone, she seemed to deflate into a girl who looked ten years younger than the tough detective Castle was used to encountering, her shoulders slouched, her brow furrowed, and a pout on her lips. After a few seconds, she noticed his presence for the first time, shaking her head as her eyes landed on him. He didn't want to interrupt her thoughts, so he stood quietly, allowing her to break the silence.

She was quiet for a moment, searching his eyes, before she finally spoke. "Well, that was… unexpected," she summed up.

"You can say that again," he answered, flopping down in his chair.

Both of them sat quietly for a few moments, staring into nothingness as the precinct's life continued without them.

"Did she tell you everything?" Kate's question shook him out of his reverie.

"God, I hope not," he said, a shiver running through his body.

"Ew, Castle, thank you for that image," she reprimanded, scrunching her nose in that adorable way he loved. "I meant their story."

"She says that they met in person at the hospital when… you know," he said casually, not wanting to directly reference Kate's shooting, "and that they've talked a couple of times since then to _exchange parental advice,_ " he finished, mimicking quotation marks in the air with a grimace. "Apparently, those calls eventually evolved into something more, and… I didn't want to know any more."

An awkward silence descended upon them once more, until a whisper from Kate broke it.

"Do you think they're serious?"

Castle didn't want to think about that. The fact that their parents were together was pretty much the end of any romantic development between him and Kate. Their own parents had robbed them the opportunity to be together.

"I don't know," he answered, his expression suddenly turning serious. "Look, my mother falls in love easily, and that's caused her trouble on numerous occasions. And I know that I complain about her a lot, but… I don't want her to go through another heartache again. She deserves to be happy, and your father's a good man."

"You barely know him. How can you tell?" Kate asked, the saddened expression on her face nearly breaking his heart.

"Because I know you," he shrugged, looking intently at her. "And if you take even a little bit after your father, I know he has to be an extraordinary man."

At that, she raised her head, and as her eyes met his, it was as if an electric current was surging between them, and he felt like all the air had left his lungs. Suddenly, their eyes widened as they took simultaneous deep breaths, both seeming to remember the original topic of the conversation. Castle slumped back in his chair as Kate buried her head in her hands, groaning.

"Hey, are you okay?" Castle inquired. "I know this can't be easy for you."

Kate turned to him again, an indecipherable look on her face.

"Don't take this the wrong way; you know how much I like Martha, but… yeah, it's difficult…" she trailed off, lost in thought.

"Kate, I'll understand if you don't want to come tonight. I'm sure they will, too."

"No, you're right. They deserve to be happy. My dad has been through a lot, too, and I want to be supportive. It's just that… why now? Everything's been so good between us lately!" she blurted out.

As soon as the words left her lips, her hands flew up to her mouth, and she squeezed her eyes shut. The blush that crept up her neck indicated to Castle that she definitely wasn't talking about herself and her dad anymore. She was obviously uncomfortable, embarrassed by her accidental admission, and Castle decided to not acknowledge what she'd said, changing the subject instead.

"Don't you think it's very sudden? They don't tell us they're together, and out of the blue, they insist on seeing us to discuss something important with us. I wonder what it is," he mused.

"Do you think they're okay? If it was a health issue, they would have told us sooner, right?" she questioned, appearing increasingly worried.

"Maybe she's pregnant!" Castle joked, in his patented move to lighten the mood.

His tactic worked, as usual. The corners of Kate's lips curved slightly upwards, his reward for a well-timed joke. "It could be, Castle. Imagine that, we're going to have a baby brother or sister!" she tossed offhandedly.

Castle's jaw dropped comically at her remark. Kate turned her attention to the computer screen with a mischievous twinkle in her eyes, having managed to turn the tables on him.

"Maybe we should call for backup," he said after a pause, already pulling his phone out of his pocket again.

"What do you mean?" Kate questioned.

He didn't answer, focused on the text message he was typing furiously.

"I'm sending Alexis ahead of us. She can test the waters, see if it's a trap."

Kate's only response was one of her signature eye rolls.

Not thirty seconds after sending the text, Castle's cell chirped with an alert. Holding the phone so Kate could see the screen too, they read the words together, taking a second to process them, then sharing a puzzled look.

 _What, and crush Gram's plan? No way! Have fun at dinner. Oh, and good luck ;)_

* * *

 _A/N: Once again, thanks to encantadaa for her beta work and awesomeness in general_


	2. Chapter 2

It was bizarre, walking up to the door of his own home and knocking, as if he were a guest. Yet here he was, doing just that. Castle was strangely nervous, which is why he'd suggested that he and Beckett arrive together. After the most tense elevator ride of his entire life, they finally reached the door of the loft.

"We need an action plan," he said in a hushed whisper, stopping short of knocking on the door and turning to Kate, determination in his eyes.

"For what? They're our parents, Castle, not the enemy," Kate said, rolling her eyes.

"You clearly haven't seen my mother when she's on a roll."

"Will you knock already?" she ordered, losing her patience.

The writer turned around again, raising his fist to knock, but he suddenly thought better of it, reaching inside his pocket and pulling out his keys. Kate shot him a questioning look, and he shrugged in response.

"What? As far as I know, this is still my home." As he turned the key in the lock, he muttered, "They'd better be decent."

The only indication that Kate heard him was a little shove.

"Mother, we're home!" he announced, swinging the door open widely.

* * *

Within minutes of Kate and Castle's arrival, the four of them had come to sit at the living room table. They were sharing a home-cooked dinner, courtesy of the combined efforts of Martha and Jim. Kate, of course, had showered it with compliments, which were immediately combated by Castle's remark about the possibility of dying of food poisoning. Kate had immediately kicked him under the table when he made that comment- joking might be his coping mechanism, but all it was doing was annoying her on a night that she was already tense enough.

Martha and Jim sat side-by-side at the table, while Kate and Castle sat directly across from them. Throughout the entire meal, the four of them had been playing a little game, which consisted in averting their eyes from the others while studying the pair on the other side. Kate was sure she was winning. Or at least, she hoped she wasn't as obvious on her scrutiny as the other three were. There was a tense undercurrent to every interaction, and the conversation was not progressing, filled with awkward pauses and forced pleasantries. Neither pair wanted to say anything that could cause further discomfort to the other, which left the group with very few safe topics.

"So, how are things at the precinct?" Martha asked, trying to force the conversation along. "Any interesting cases lately?"

"Same as always… although you know how we seem to attract the weird cases," Beckett answered with a polite smile.

There was a lull in the conversation, as everyone busied themselves with chewing their steaks distractedly. Martha and Jim shared a nervous look, then laced their fingers together atop the table. The simple gesture caused Castle to drop his fork on the table in surprise, producing a metallic sound that amplified in the quietness of the loft. Kate swallowed noisily, her eyes locked on their parents' hands. Martha smiled again at Jim, glancing at the bewildered duo across the table out of the corner of her eye before focusing back on her dinner.

Kate tore her eyes from the older couple, shifting her gaze to Castle, who was staring at their parents' hands, working the muscle in his jaw, as if he were trying to decide whether to speak or not. Finally, with an exasperated sigh, he broke the silence.

"Aren't we going to address the elephant in the room?"

"Richard…"

"No, Mother," he continued, agitated. "You told us about your… relationship over the phone, then you invite us to my own home with barely a few hours to prepare ourselves, and now you behave like nothing has changed. It's not right, it's not nor—"

"Richard, calm down," his mother interrupted.

"I can't calm down. Not until you admit that this is twisted, even for you, Mother."

Kate had never seen Castle this angry before. In fact, the expression on his face was completely new to her. Over the years, she had seen him happy, worried, sad, apologetic, playful… even hurt. This heated anger was new, though. The last time she'd seen him angry, it had been at her, and Kate would never forget the coldness in her partner's eyes when he walked away from her that day at the swings, when she came back from her father's cabin. Tonight, however, there wasn't any coldness in his features, only pure, heated rage.

Martha tried to soothe him the best she could, speaking calmly and resting a hand on his son's forearm across the table, but Castle wouldn't allow it, shaking her off as his eyes shot daggers at her. Kate and Jim watched awkwardly as the argument between mother and son grew in intensity. Finally, Martha asked her son to accompany her to his office, excusing them both from the table.

An office with bookshelves as walls didn't provide much privacy, though. Their argument could still be heard clearly from the table, although slightly muffled by the shelves. Kate sat quietly, avoiding looking at her father, and neither spoke for some time, too stunned to utter a single word.

"Katie," Jim finally started, tentatively. "I know you're thinking about your mom, and I want you to know that…"

"This isn't about Mom. She would want you to be happy," Kate answered drily.

"I know, and I'm sorry about today… I really think we should talk. Rick's right, this is getting out of control…"

"Dad, I don't want to talk about it, alright? Not here. Not now," she resolved.

Father and daughter fell silent again, sitting awkwardly at the table as the Castle-Rodgers earthquake continued to escalate behind the office's closed door. It was becoming increasingly difficult to discern what they were saying, because both of their voices had risen in volume, their quasi-screams overlapping. It sounded as though Martha was trying to convince her son to return to the table with their guests, and after a while, Castle finally agreed.

"But I want you to know that I'm not doing this for you, but for Kate. I won't leave her alone with this mess," Castle assured, emphatically. "If she wasn't here, I'd be long gone by now."

No sooner had he spoken these words than the office door flew open, and Martha and Rick strode purposefully towards the table, chins held high and shoulders squared. The resemblance between mother and son had never been stronger, matching blue eyes aflame, and both the gestures and the posture of one were a reflection of the other's.

"I'm sorry you had to hear that," Castle apologized, retaking his seat beside Kate.

An awkward silence descended upon the table once more. Castle kept his eyes carefully focused downward, busying himself in stabbing his steak repeatedly. On the other side of the table, her father was absently twisting the napkin on his lap, while Martha alternated between gazing reassuringly at Jim, offering understanding looks to Kate, and staring furiously at her son. After a moment, Kate realized that she was reducing her piece of bread to crumbles, her food sitting untouched on her plate.

"Look, Jim, I want you to know that I'm not irritated with you," Castle finally offered, breaking the silence. "You're a good man, and I wish you all the happiness you can get."

Jim took his time before answering Castle, and Kate could tell that he was thinking carefully about his words, judging by the pensive look on his face. Her father finally raised his head, wearing what Kate called his "lawyer face," looking serious and inscrutable.

"Rick, your mother and I are old enough to know what we want. We've decided to be together, and things have been great so far. You have to understand that—"

"Understand?" Kate interrupted abruptly. "We are the ones who need to understand you? And what about you? After everything we've been through, you do this to us. You stab us in the back, and then ask for ourrespect and empathy."

"Katie…"

"No, Dad. Let me finish. You want me to be glad for you? I am," she said, gradually growing louder as she spoke. "I want you to be happy, you know that. But don't ask me to be okay with it when you tell me that you're dating the mother of the man I'm in love with!"

Kate's volume had increased so much that she practically screamed the last sentence, and her words echoed throughout the kitchen. Castle stared at her with a mix of bewilderment and awe in his eyes, gaping like a fish, and Martha and Jim watched her with knowing smiles on their faces. She closed her eyes and dropped her head, simultaneously embarrassed and defeated by her admission.

"That wasn't that hard, was it?" Martha said softly.

Kate's head shot up so quickly that she almost felt dizzy. She narrowed her eyes at Martha, trying to decipher a possible hidden meaning behind her words. The older woman said nothing more, though, releasing Jim's hand. Their parents scooted their chairs back to their normal positions, putting some space between each other as they beamed proudly. As soon as Kate's gaze landed on Jim, he smiled, shrugging apologetically.

Kate's neurons were short-circuiting, her mind racing as she tried to understand what was going on. Next to her, Castle was the one to finally put the pieces together.

"Wait, wait, wait… You're not together?" he asked incredulously.

Jim and Martha chuckled softly, exchanging a knowing look.

"Of course not!" Martha answered, waving her hand dismissively, as if the notion were ridiculous. "How could you fall for that so easily? My acting skills must be improving with age… like a good wine, huh?"

Martha laughed again, but stopped when she noticed the incredulous look both Castle and Kate were giving her.

"Come on, Jim, let's leave these two alone," she said, smiling at the older man.

Their parents rose from the table and headed for the door without another word, leaving their children completely speechless behind them.

"I'm going to an art gallery opening with some friends. Would you like to come?" Martha asked Jim, gathering their coats.

"No, thanks, Martha; I'd better head home. I have an early start tomorrow," he replied. "But maybe we can share a cab, if that suits you."

"Perfect. See you later, kiddos!" she said over her shoulder, winking at them as she closed the door after her.

The click of the lock reverberating throughout the wide living room was the only noise in the whole loft. Several moments passed, with Castle and Beckett sitting frozen. Kate finally turned to Castle, her eyes wide.

"That's been… it was… this was an intervention!"

* * *

Several minutes had passed since Martha and Jim left, but Kate and Castle hadn't spoken more than a handful of words to each other since. Neither of them seemed to know how to break the ice, still trying to process the roller coaster of emotions they'd been taken through throughout the day. After sitting in stunned silence for a few minutes, Kate had finally suggested that they clean the kitchen, standing to take her plate to the sink. Castle followed suit, and the two focused on the task at hand.

Kate was still divided between anger and mortification. She was supposed to be one of the best detectives in town, and her own father was able to deceive her without blinking an eye. And to make things worse, the older couple had led her to confess something she had been trying to hide for the better part of the year. Well, if she was honest with herself, she'd been denying it for much longer than that.

 _Awkward_. That was the feeling that summed up the whole evening. Kate still wasn't sure what to say, let alone what to think. Thankfully, Castle finally broke the silence.

"We need to talk," he said.

"I guess we do," she answered with a sigh, setting the last glass by the sink.

He cleared his throat loudly and closed the dishwasher door, turning to face her. "Did you mean it? The part about being… in love with me," he asked, hesitantly.

She slowly took a step towards him as thoughts raced through her brain. There were so many things she wanted to tell him, but she knew that there was something she needed to confess first.

"There's something I have to tell you." She paused, averting her eyes to the ground, unsure how to continue.

"Kate, you can tell me anything, you know that," he reassured.

She took a deep breath, summoning up the courage she needed to continue. "I heard you," she finally said, pronouncing the admission that she'd been rehearsing in her mind for months. "That day, at the cemetery. I heard you. I remember everything."

She heard his sharp intake of air, but he said nothing, and the silence stretched for several moments. Finally, Kate raised her head and met Castle's eyes. She could see the tenderness and sadness written into them, but what broke Kate's heart was the hurt deeply rooted there. He instantly dropped his gaze, as though he couldn't take the way she was looking at him.

"All this time…" he muttered, taking an involuntary step back, as though he had just been punched.

Kate didn't allow him to go too far, reaching for his hand and giving it a little squeeze as she pulled him back toward her. "I'm so sorry, Rick. I didn't tell you sooner because… I was scared, okay?" she murmured, dropping her eyes to the ground. "I was terrified that you would have changed your mind after the summer, or that you only said that because you thought I was dying."

"How can you think…? Kate, if you didn't feel the same way, you just—"

"No!" she interrupted. "Don't think that even for a second. I didn't say anything because I wanted to be better. I wanted to be ready for the relationship I've always wanted. With you. Only with you."

Castle was studying her intently, taking everything in. Judging by the look of utter disbelief on his face, though, he obviously was having trouble trusting her words.

"Rick, I've been seeing a therapist since I was shot. I wanted so badly to leave my shooting and my mother's case behind me. Both of those things been preventing me from moving on. But I'm almost there now."

Kate kept her eyes locked with Castle's, hoping he was able to everything written in them that she couldn't express with words. She took one more step forward, now only inches away from him.

"Remember the other day, when we were watching your mother's 'one-woman play?'" Castle nodded. "That's when I saw that I already have a place in your family, in your life," Kate affirmed. "As I watched your mother talking about you, and you pretending to be bothered, I realized I didn't want to go back to my empty apartment. I want to be with you, Castle. I love you."

Castle's factions changed entirely at that. Until that moment, his entire body was tense, his back upright, and one foot positioned carefully behind him, ready to flee at any moment. But he instantly relaxed when he heard Kate's last words, seemingly shrinking a couple of inches as he let out all the air in his lungs, simultaneously releasing the tension in his shoulders. The hand Kate was still holding turned until their fingers were intertwined, and his eyes, always so expressive, were now full of adoration.

"You… you love me?" he stammered, his voice barely a whisper.

Kate chuckled nervously and stepped even closer.

"Of course I love you," she assured, encircling his shoulders with her arms. He reciprocated by resting his hands on her waist. "That's why I felt like I was drowning when my dad told me he was dating Martha. Something stirred inside me, and the few bricks that were left of that damn wall were sent tumbling."

"Can we ditch the wall metaphor now?" he asked, pulling her closer. "I can't even walk by a construction site without shivering."

"Of course," she laughed.

The world seemed to stop spinning for a second as they closed the distance between them,their lips finally meeting in a sweet kiss. The soft pressure of Castle's lips against her own was everything she always dreamed it would be, and then more. They only broke the kiss when the wide grin that appeared on Kate's face made it impossible to continue. She looked into Castle's eyes and saw a reflection of the same joy.

"My mother makes a living out of it, but who would have thought that your father would be such a good actor?" Castle mused, lips against her temple, as she rested her forehead on his cheek, too content to step out of his arms just yet.

"Shut up, Castle. I think I'm going to have nightmares about this for months."

"Don't worry, I'll distract you at night," he offered, his tone serious.

"Always the gentleman," she chuckled, pulling back to look at him.

This time, when she rose to her tiptoes to kiss him, she didn't care about keeping it chaste, and Castle responded enthusiastically, almost lifting her off the floor. The next time they saw their parents, they would give them a piece of their minds. But that would be the next day. At the moment, they had better things to do.


End file.
